class Doctor:
    def __init__(self, **args):
        self.name = args['name']
        self.post = args['post'] if 'post' in args else ''
        self.group = args['group'] if 'group' in args else ''

    def __dict__(self):
        return {
            'name': self.name,
            'post': self.post,
            'group': self.group,
        }